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arXiv · 0804.0925

Computing ODE Symmetries as Abnormal Variational Symmetries

Paulo D. F. Gouveia·Delfim F. M. Torres
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Abstract

We give a new computational method to obtain symmetries of ordinary differential equations. The proposed approach appears as an extension of a recent algorithm to compute variational symmetries of optimal control problems [Comput. Methods Appl. Math. 5 (2005), no. 4, pp. 387-409], and is based on the resolution of a first order linear PDE that arises as a necessary and sufficient condition of invariance for abnormal optimal control problems. A computer algebra procedure is developed, which permits to obtain ODE symmetries by the proposed method. Examples are given, and results compared with those obtained by previous available methods.

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Paulo D. F. Gouveia, Delfim F. M. Torres. 2008-04-06. Computing ODE Symmetries as Abnormal Variational Symmetries. https://doi.org/10.1016/j.na.2008.10.009

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